jakarta ee - How to calculate a file size from URL in java

Question

I'm attempting to get a bunch of pdf links from a web service and I want to give the user the file size of each link.

Is there a way to accomplish this task?

Thanks

Answer 1

Using a HEAD request, you can do something like this:

private static int getFileSize(URL url) {
    URLConnection conn = null;
    try {
        conn = url.openConnection();
        if(conn instanceof HttpURLConnection) {
            ((HttpURLConnection)conn).setRequestMethod("HEAD");
        }
        conn.getInputStream();
        return conn.getContentLength();
    } catch (IOException e) {
        throw new RuntimeException(e);
    } finally {
        if(conn instanceof HttpURLConnection) {
            ((HttpURLConnection)conn).disconnect();
        }
    }
}